Java Module Manager

Eclipse-style Close Project for Maven multi-module projects in VS Code.

When you open a large Maven multi-module workspace, redhat.java (Eclipse JDT behind the scenes) imports every module and keeps compiling all of them — high CPU, high memory, slow startup. This extension lets you "close" the modules you are not working on, just like Eclipse's Close Project: closed modules are not imported and not compiled, while everything else keeps working.

Features

• Status bar: shows Java 3/20 (enabled/total). Click it to pick modules with a multi-select list — enabled modules are pre-checked.
• Explorer right-click on a module folder → Java Modules: Open/Close This Module.
• Editor right-click → opens/closes the module that owns the current file (menu label follows the current state).
• Closed modules are marked with a ⊘ badge in the Explorer (color #7A8FA3, customizable).
• Presets: save the current selection as a named preset (e.g. "order-service-dev") and restore it with one command.
• Dependency awareness:
  • Closing a module that other enabled modules depend on shows a warning — those modules would fall back to the jar in your local .m2 (possibly stale).
  • Enabling a module automatically enables its in-workspace dependencies.
• Bilingual: English / 中文, following the VS Code display language.

Usage

1. Open your multi-module Maven workspace.
2. Click Java n/m in the status bar (bottom right).
3. Check the modules you want compiled, press Enter.
4. Apply the change: Reload Window (fast, keeps compiled cache) or Clean and Restart.

Closing a module that is already imported requires a workspace clean to disappear from the Java Projects view; mere reload is not always enough. The notification offers the right button.

How it works

The extension maintains the module entries in java.import.exclusions (workspace .vscode/settings.json):

"java.import.exclusions": [
    "**/node_modules/**",
    "**/.metadata/**",
    "**/archetype-resources/**",
    "**/META-INF/maven/**",
    "**/module-i-closed/**",
    "**/module-i-closed"
]

• Only its own managed entries (**/<module-folder>/**) are added or removed — any rules you wrote yourself are preserved, and the official defaults are always ensured.
• Modules are discovered by scanning for pom.xml (plain XML parsing, no mvn invocation).
• Dependencies are read from each module's <dependencies> (not parent, dependencyManagement, or profiles).
• Closed modules are not removed from global search (grep) or the file watcher — you can still search across them, they simply do not participate in compilation and Java language features.

Settings

Color of the closed-module badge:

"workbench.colorCustomizations": {
    "javaModuleManager.closedModule": "#7A8FA3"
}

Requirements

• VS Code 1.85+
• The Extension Pack for Java (or at least redhat.java)

Related tips

• "java.import.mode": "ondemand" (redhat.java 1.5x+) imports a module only when you open a file in it — complementary to this extension and good for cold start times.

中文说明

Eclipse Close Project 的 VS Code 版，针对 Maven 多模块工程。

打开大型 Maven 多模块工程时，redhat.java（底层是 Eclipse JDT）会把所有模块导入并持续编译， CPU 和内存吃满、启动很慢。本扩展让你把暂时不用的模块"关闭"：被关闭的模块不导入、不编译， 其余模块照常工作。

功能

• 状态栏：右下角显示 Java 3/20（启用/总数），点击弹出多选框，已启用的默认勾选。
• 资源管理器右键模块文件夹 →「Java 模块: 开启/关闭此模块」。
• 编辑器右键 → 开关当前文件所属模块（菜单文字跟随当前状态变化）。
• 已关闭的模块在资源管理器中带 ⊘ 角标（颜色 #7A8FA3，可自定义）。
• 预设：把当前选择存成命名预设（如「订单服务开发」），一条命令切换回来。
• 依赖感知：
  • 关闭被其他启用模块依赖的模块时会弹警告——那些模块会改用本地 .m2 里的 jar（可能已过期）。
  • 启用某模块时自动连带启用它在工作区内的依赖。
• 中英双语：跟随 VS Code 界面语言。

使用步骤

1. 打开多模块 Maven 工程。
2. 点击右下角状态栏 Java n/m。
3. 勾选要编译的模块，回车确认。
4. 选择生效方式：重载窗口（快，保留编译缓存）或 清理并重启。

关闭一个已经被导入的模块，需要执行一次工作区清理才会从 Java Projects 视图消失， 仅重载窗口不一定够。通知里会给出对应的按钮。

工作原理

扩展维护 java.import.exclusions（工作区 .vscode/settings.json）中的模块条目， 只增删自己管理的 **/<模块文件夹>/**，你手写的其他规则原样保留，官方默认四条始终确保存在。

模块列表来自扫描 pom.xml（纯 XML 解析，不调用 mvn）；依赖只读取各模块的 <dependencies> （不含 parent、dependencyManagement、profiles）。

被关闭的模块不会从全局搜索和文件监视中排除——你仍然可以跨模块搜代码，只是它们不参与编译和 Java 语言特性。

设置

环境要求

• VS Code 1.85+
• Extension Pack for Java（或至少 redhat.java）

License

MIT